With the great development of the cell phone and the liquid crystal TV industry recently, and for responding to the increasing requirement of the liquid crystal glass substrate and the requirement of low-thermal stress processing of LCD glass substrates, the thermal rupture laser cutting method has gradually taken the place of conventional cutting methods such as abrasive cut-off diamond blades and laser melting methods, and has become the main stream of LCD glass substrates processing in the second generation of optoelectronics industry. The thermal rupture laser cutting method is distinct from the conventional laser melting method in applying the principle of thermal rupture, so that the laser heat is uniform and the thermal affecting area is small. Therefore, besides the fast processing speed, the thermal rupture laser cutting method has advantages of smooth cut face and low thermal residual stress, which cannot be achieved by abrasive cut-off diamond blades and laser melting methods.
There are two kinds of laser light sources for thermal rupture cutting in the current industry, i.e. CO2 gas laser (λ=10.6 μm) and YAG solid laser (λ=1.064 μm). A thermal field is provided on a glass substrate via a steady laser light being focused by a photo-lens, and a cooling effect is added for generating an initial crack on the edge of the substrate. The thermal and cooling fields provide a stress intensity factor field, which is large enough to make the initial crack grow at an equal rate and the cutting effect is finally formed. However, the conventionally provided sequence of the thermal rupture stress required by the initial crack on the edge of the substrate has difficulty in providing an initial crack successfully at a start hole of the cutting path on the substrate for getting a substrate with a random hollow shape.
In order to overcome the mentioned drawbacks in the prior art, a cutting device for cutting a hard-brittle material is provided in the present invention.